Re:Tesla Roadster
by thinkloop on Friday November 17, 2017 @03:48AM
(#15720281)
Shifting gears? Why does it have an advantage?
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Re:Tesla Roadster
by vanderZwan on Friday November 17, 2017 @04:10AM
(#15720395)
Tangent: please don't downvote someone asking questions, people. I for one had not considered that electric motors have no gears to shift, and wondered "surely both cars are automatic? Does Tesla have a patent on a faster automatic transmission or something?" so I appreciated someone asked.
Teslas don't need gears since they use electric motors. So there is literally no time spent shifting gears.
See https://www.quora.com/Why-don%E2%80%99t-Tesla-cars-need-a-ge...
The original Veyron could change gears in 8ms, and will, IIRC hit 60 in 2nd. Changing gear isn't going to be a considerable part of the time here.
Wikipedia https://en.wikipedia.org/wiki/Bugatti_Veyron states that the original Veyron gearbox could change gears in 150ms, so it is a considerable part of the time.
While the gear are shifting the engine RPM must go down then up; the 8ms figure certainly doesn't account for the complete sequence.
The Veyron does 70 in first gear. I don't know if its 0-60 times require a gear change or not.
The basic idea is that it is wasting time.
But this is no longer a factor as the gear change is instantaneous with Automatic GearBox.
Electric cars do not have a gearbox and just have one rotor. This does place them in a disadvantage when starting though as there acceleration is affected. Formula E cars, have started using a 3 gearbox for their cars in order to have a faster start.
So it is possible that the Roadster does have a gearbox.
Re:Tesla Roadster
by drcoopster on Friday November 17, 2017 @10:33AM
(#15722739)
Tesla tried a gearbox in the first Roadsters, and it didn't go so well.